How do you solve #2x + 1 = 9#?

1 Answer
Jul 27, 2015

Isolate #x# on one side of the equation.

Explanation:

In order to solve this equation, you have to isolate#x# on one side of the equation. You can do that in two steps.

First, add #-1# to both sides of the equation

#2x + color(red)(cancel(color(black)(1))) - color(red)(cancel(color(black)(1))) = 9 - 1#

#2x = 8#

Finally, divide both sides of the equation by #2# to get

#(color(red)(cancel(color(black)(2))) * x)/color(red)(cancel(color(black)(2))) = 8/2#

#x = color(green)(4)#

And there you have it. If you double #x# and add one, you get nine.